Immutable cache array

[peakji]

Implemented two minor changes that might give us a performance gain:

• No need to reverse the array in C++ land, this will avoid creating slow arrays with holes.
• Remove .pop() operations in JS land, leave the cache array immutable.

I haven't run the benchmarks yet, @vweevers is there any benchmark script suitable for this one?

Note: I forked this brach from remove-fast-future, I'll rebase after #638 gets merged.

[peakji]

I see tests failed on checking the cache size after calling .end(), is there a particular reason to manually delete the cache array here?

AFAIK, deleting properties of a class is not a recommended practice since it might affect V8's hidden class.

[vweevers]

I haven't run the benchmarks yet, @vweevers is there any benchmark script suitable for this one?

Was working on that but I fell into a rabbit hole 😄 Climbing out!

[vweevers]

Climbed out. No actual benchmark written yet, only goodies: keyspace, zipfian-integer, uniform-integer, pseudo-random-buffer and pseudo-math-random.

[ralphtheninja]

@vweevers you're on a roll!

[peakji]

My little benchmark script shows these changes just made things slower 😢: #638 (comment) .

I'm closing this PR now but feel free to reopen.